Dense Inner-Cities Give Self-Driving Cars a Reality Check

Google has abandoned the idea of giving humans partial control over autonomous vehicles, removing the steering wheel and brake pedal from current designs. This leave practically no room for machine error, meaning Google has given itself a very difficult task. (The company reasoned that humans couldn't be trusted to keep their attention on road conditions, especially since self-driving cars encourage drivers to take their attention away from driving in the first place). And while Google impressed many engineers with the progress made on its autonomous car, driving conditions in the city pose daunting challenges not present on the open roads where Google's cars are currently tested.

What's the Big Idea?

Lone highways in the southwest US do not change very often (where Google's cars have been tested). Driving them is predictable, but city streets are not. Chris Urmson, director of Google's project, said: "Obviously, the world doesn’t stay the same. You need to be able to deal with things like temporary construction, and so we’ve been putting a lot of effort into understanding the semantic meaning of the world." While humans use social context to differentiate between similar physical events--is the person waving their arm in the street a traffic cop or a trouble maker?--computers have a harder time at it. Experts say it could be decades before autonomous cars are ready for cities.